A cup holder for retaining a beverage container and the like in a stable state is equipped in a passenger compartment of an automobile. As such a cup holder, ones having a supporting member capable of supporting a side surface of the container inserted into a receiving portion of a holder main body are known. Typically, in the cup holder having the supporting member, the container such as a PET bottle having various dimensions and shapes that is inserted into the receiving portion can be retained in the stable state by the supporting member advancing into the receiving portion. Further, the container such as the PET bottle can be taken out from the receiving portion as a result of the supporting member retracting from the receiving portion.
As shown in FIG. 6, a cup holder 50 disclosed in Japanese patent No. 3725505 includes a holder main body 51 having a receiving portion 51a into which a beverage container B1 is to be inserted, and supporting members 52 capable of advancing into and retracting from the retaining portion 51a of the holder main body 51. Each of the supporting members 52 is provided capable of rotating with an axial line O along a horizontal direction as a center, and is biased such that its portion lower than the axial line O advances into the receiving portion 51a. When the beverage container B1 having a protrusion and recess pattern on a side surface is to be taken out from the receiving portion 51a, a protrusion B1a of the beverage container B1 makes contact with guide portions 52a of the supporting members 52. Each of the guide portions 52a has a shape with which a force F from the protrusion B1a acting on the guide portion 52a is oriented toward a lower side than the axial line O. With the force F being oriented toward the lower side than the axial line O, a moment is exerted on the supporting members 52 in a direction that causes the guide portions 52a to retract from the receiving portion 51a (a counter-clockwise moment). Due to this, the beverage container B1 having the protrusion and recess pattern on the side surface can smoothly be taken out from the receiving portion 51a of the holder main body 51.
As shown in FIG. 7A and FIG. 7B, a cup holder 60 disclosed in Japanese utility model No. 3137651 includes a holder main body 61 having a receiving portion 61a into which a beverage container is to be inserted, and a supporting member 62 capable of advancing into and retracting from the receiving portion 61a of the holder main body 61. The supporting member 52 is configured of an upper piece 621 having its upper end supported rotatably by a side portion of the holder main body 61, a lower piece 622 having its upper end linked rotatably to the upper piece 621 and its lower end sliding on the side portion of the holder main body 61 in an up and down direction, and a spring 63 that is attached to a linking portion of the upper piece 621 and the lower piece 622 and that biases the linking portion to advance in a direction approaching a center axis of the holder main body 61. A stopper surface 621a that restricts a rotation of the lower piece 622 relative to the upper piece 621 to be within a predetermined range is formed at a lower end of the upper piece 621. When the beverage container is inserted into the receiving portion 61a, the linking portion of the upper piece 621 and the lower piece 622 is pressed by a side surface of the beverage container, and the supporting member 62 is retracted to a position shown in FIG. 7B from its most advanced position shown in FIG. 7A.